1. Field of the Invention
The present invention relates generally to gas leak detection by odorization to improve safety during transport, delivery, and end use. In particular, the invention relates to leak detection by odorization for gaseous fuels, most notably hydrogen fuel.
2. Background of the Technology
Hydrogen is considered by many to be the fuel of the future due to its high availability, very high calorific value, wide flammability limits and non-polluting nature. However, the highly combustible nature of hydrogen poses a great hazard creating a number of problems with its safety and handling. Therefore, leak detection in hydrogen systems is critical for any hydrogen application. Pure hydrogen is a colorless and odorless gas. There are many different types of mechanical ‘hydrogen gas detectors’, but as with any mechanical device, these detectors are also prone to mechanical failure. Even the most durable hydrogen sensors are too costly and cumbersome for automotive use. Existing sensors are too easily jostled, and their reactive metals, which include expensive noble-metals such as palladium, are ruined by contact with gases and particles that are common on the road. Considering the dangers associated with an extremely flammable gas like hydrogen, it becomes necessary to have an odorant for this fuel just as there are mercaptans for detecting natural gas leaks, accepted widely as a means of maintaining safety.
While gasoline, diesel, gasoline hybrid, and diesel hybrid vehicles are prevalent and electric and fuel cell vehicles are becoming more common in the transportation industry, vehicles do not currently incorporate hydrogen odorants or odorant removal systems. Some of the shortcomings and disadvantages associated with gasoline and diesel vehicles include pollution and dependency upon imported oil. Current electric vehicles, unfortunately, require a long battery charge time when not in operation. The main barrier to a widespread adoption of fuel cell vehicles is a lack of re-fueling infrastructure.